Taxonomic implications of unusual zoospore discharge in an isolate of Saprolegnia unispora

We have isolated a strain of Saprolegnia unispora whose primary zoospores e xhibit a range of motilities extending from slow quivering to moderately ra pid swimming depending on their sporangium of origin; Secondary spores swim normally suggesting that different subcellular mechanisms may control prim ary spore swimming than control that of secondary spores. A digitized video tape of this spore behavior can be viewed on the first author's web page ( http://www.uncwil.edu/people/padgett). This behavior is similar to that pre viously reported for at least two species of Isoachlya suggesting that Mis genus, formerly brought into synonymy with Saprolegnia, might warrant reins tatement after further study.